1. Field of the Invention
The invention relates to a cycle, in particular a bicycle, comprising a frame with a seat tube, a height-adjustable seat that is connected to the seat tube, which seat tube comprises a portion that is at an angle from 0 to 45xc2x0 to the vertical direction, with the seat being conneted to said portion and being located in front of the seat tube, a rear wheel that is connected to the frame, a front fork in which a front wheel is present and that has a pivoting connection with the frame, a handlebar with a steering tube with one end fastened to the front fork, and handgrips that are part of the handlebar and are fastened to the steering tube. Due to the presence of a handlebar that is directly connected to the front fork it is possible to manufacture the cycle in such a way that a user of the cycle can assume a comfortable upright position on the cycle. The term xe2x80x9ccyclexe2x80x9d here should be understood to mean a bicycle, a tricycle, or a cycle with more wheels than three, both with and without a motor.
2. Prior Art
Such a cycle is known from CA-A-2104836. The known cycle allows the user to assume a comfortable upright position on the cycle due to the presence of a handlebar that is directly connected to the front fork. For the height adjustment of the seat the known cycle has a frame with a bar with a portion that slopes upward in which a tube can be slid. On front of the tube that extends out of the bar a seat with a back support is fastened. On behalf of the required strength of the connection between the tube and the bar the tube should always be slid at least to a certain extend into the bar. This limits the adjustment range of the seat. If one then also wishes to facilitate a relatively low position of the seat, the consequence is that the slanted portion must be relatively short, so that the adjustment range is even more limited.
An objective of the invention is to produce a cycle of the type described in the preamble in which the construction of the cycle realises a better height adjustment of the seat than is the case with the known cycle. To this end the cycle according to the invention is characterised by the fact that the seat can be slid along the seat tube. By connecting the seat in front of the seat tube with the seat tube itself, less limitations result in terms of the length or height of the mainly vertically directed portion of the seat tube than in the known cycle, allowing a greater adjustment range of the seat than is the case with the known cycle.
Though it is indeed true that in DE 195 11 629 A1 en DE 44 03 706 C1 bicycles are known that have a mainly vertical seat tube and a seat that is in front of the seat tube, these known bicycles are so-called recumbent bicycles in which the user assumes more of a recumbent position than a sitting position and in which no handlebar is fastened to the front fork but, instead, steering takes place with the help of handles that are present near the seat. Such recumbent bicycles have a low sitting/recumbent position and are suitable for more physically active people. These recumbent bicycles do not offer the convenience and comfort of bicycles with a conventional handlebar in which the user assumes a sitting position.
In addition, from DE 297 19 662 U1 and U.S. Pat. No. 5,509,678 bicycles are known that are provided with a conventional handlebar with the seat being slidable along a tube of the frame. However, the frames of these known bicycles do not have a mainly vertically directed seat tube, and in these bicycles the seat is not in front of the seat tube but above a virtually horizontal tube of the frame. In these known bicycles, too, the user assumes more of a recumbent position than a sitting position.
An embodiment of the cycle according to the invention is characterised by the fact that the cycle comprises a bottom bracket axle that is connected to the frame at a position that, during use of the cycle, is lower than an imaginary line which extends parallel to and is 10 cm above an imaginary line through the wheel axles of the front and rear wheel. This makes it possible for the user to assume an even more comfortable upright position on the bicycle. In addition, a low bottom bracket axle permits a construction of the cycle in which a low mounting height is possible. The minimal mounting height is determined by the height of the bottom bracket axle.
Preferably the position of the bottom bracket axle is lower than the imaginary line through the wheel axles of the front and rear wheel.
Preferably the cycle also has a back support that is connected to the seat and comprises two parts which can be adjusted in relation to each other. The back support can be solidly fastened, for example by means of a connection element, to the seat or the back support can be adjustable in relation to the seat. The two parts of the back support are located preferably on top of each other with the upper part being adjustable in terms of height in relation to the lower part.
An embodiment of the cycle with a favourable fastening construction of the seat and/or the back support to the frame is characterised by the fact that the seat and/or back support is/are connected to a profile that can be slid along the seat tube and can be. fastened to the seat tube. The profile being able to slide and be fastened can be favourably realised by a construction in which there is a bracket on either side of the seat tube that extends lengthwise in relation to the seat tube, with the profile between the brackets and the seat tube being able to be slid, with the brackets clamping the profile securely against the seat tube.
To obtain increased comfort in a cycle the wheels can be fastened to the frame with springs. From the American patent specification number U.S. Pat. No. 4,789,174 a rear wheel suspension assembly of a bicycle is known in which the bicycle has a bottom bracket axle that is connected to the frame, and the axle of the rear wheel is coupled with a wheel bearer that has a bottom and top end, with a first wheel guide arm being connected to the bottom end in a pivoting manner, which first wheel guide arm is connected with its other end in a pivoting manner to the frame at a point that is a short distance from the bottom bracket axle of the bicycle, and in which on the top end of the wheel bearer a second wheel guide arm with an end is connected in a pivoting manner, which second wheel guide arm is connected with its other end in a pivoting manner to the frame. A disadvantage of this wheel suspension is that, because the center of rotation of the first wheel guide arm in relation to the frame is a distance away from the chain wheel on the bottom bracket axle, when the chain moves it moves a considerable distance such that it becomes difficult to utilise a chain guard.
An embodiment that does not have this disadvantage is characterised by the fact that the first wheel guide arm is connected with its other end to the frame such that it can pivot around an imaginary axis through the bottom bracket axle of the cycle. Thus the chain moves a smaller distance when it operates, so that a chain guard can be used more easily.
It should be remarked that this embodiment can also be used independently of the above described construction of the seat on the frame, on any cycle at all, thus keeping the option open of splitting this advantageous construction from the patent application at hand and claiming it independently.
In known cycles on each side of the frame there is a rear wheel suspension assembly, so that each of the wheel bearers have a notch for picking up the axle of the rear wheel, which notch comprises a mainly vertically running slot that is open at the bottom. In these open slots on the bottom the rear wheel and its axle can be slid and then fixed in place on the wheel bearers. To improve the adjustment options of the rear wheel in such a construction an embodiment is characterised by the fact that at least one of the notches is provided with a mainly horizontally running further slot that connects to the top end of the vertical slot.
It should be remarked that this embodiment, too, can be used independently of the above mentioned constructions, on any cycle at all, and that for this reason the option is kept open of splitting this advantageous construction from the patent application at hand and claiming it independently.
Cycles are known in which the handlebar comprises two mainly parallel steering tubes, each with a free end that has a handgrip. To be able to adjust the position of these handgrips these steering tubes can be made so that they can pivot. In the adjustment of the position of the handgrips it is desirable that the handgrips be placed mirror symmetrically in relation to each other. An embodiment in which the adjustment of the steering tubes and thus the handgrips is better possible is characterised by the fact that the steering tubes are coupled with each other by a synchronisation mechanism that converts an angular rotation of one of the steering tubes into an equal sized but opposite angular rotation of the other steering tube.
Here once again it should be remarked that this embodiment, too, can be used independently of the above mentioned constructions, on any cycle at all, and that for this reason the option is kept open of splitting this advantageous construction from the patent application at hand and claiming it independently.
A favourable embodiment of the synchronisation mechanism is characterised by the fact that the synchronisation mechanism comprises at least one coupling element that is connected with both steering tubes, with the connection with one of the steering tubes, in terms of the lengthwise direction of the cycle, being present on the front of that steering tube, with the connection with the other steering tube being on the back side of that steering tube. To be able to transfer the angular rotation of the one steering tube to the other steering tube the connection between the steering tubes must not be stiff. For this purpose the coupling element can be connected to the steering tubes in a pivoting manner or the coupling element can be flexible, for example in the form of a cable.
Another embodiment that requires little space and is uncomplicated is characterised by the fact that the synchronisation mechanism comprises two coupling elements which are each separately or else jointly formed by a cable and which cross each other between the steering tubes. This embodiment is particularly desirable if the coupling elements are executed as cables. Since cables can only transmit drawing force, to facilitate angular rotation in two directions it is necessary to use two cables. The two coupling elements can be made of one cable here, with the cable then being of an 8-shape.
Another embodiment of the cycle according to the invention is characterised by the fact that the cycle comprises a mudguard that is formed by an extrusion profile that has on its sides notches over the entire length for containing dress guards and/or electrical cables. This makes it possible to better fasten or guide dress guards and/or electrical cables to the cycle.
Here it should also be remarked that this embodiment, too, can be used independently of the above mentioned constructions, on any cycle at all, and that for this reason the possibility is retained of splitting this advantageous construction from the patent application at hand and claiming it independently.
Another embodiment is characterised by the fact that the cycle has a steering head comprising a housing fastened to the frame and an axle that pivots in the housing that is fastened to a front fork of the cycle, such that the handlebar with the front fork and the front wheel of the cycle can be turned, with the axle being at an angle in relation to the front fork in such a way that the intersection of an imaginary line through the axle and the ground is closer to the contact surface of the front wheel with the ground than the intersection of an imaginary line through the front fork with the ground. This increases the stability of the cycle in comparison with a cycle in which the axle runs parallel with the front fork. This favourable effect is greater the more the front fork is placed flat.
In addition, it should be remarked that this embodiment can be used independently of the above mentioned constructions, on any cycle at all, and that for this reason the possibility is retained of splitting this advantageous construction from the patent application at hand and claiming it independently.
Another embodiment is characterised by the fact that the cycle comprises a kickstand that can pivot between a folded-in position and a folded-out position and that the cycle has a locking mechanism for locking the kickstand in the folded-out position, which locking mechanism is housed in a tube of the frame.
A favourable embodiment of this is characterised by the fact that the locking mechanism comprises a revolving cam that can pivot between a release position and a lock position, in which latter position the cam encloses a pin present on the kickstand, so that using a lock either on the cycle or externally the cam can be locked in place.
Another favourable embodiment of this is characterised by the fact that the cam pivots around an axle that is secured by a pin that is fixed in place with a bolt, which bolt is located between parts of the cycle such that the bolt is only accessible to be removed after the cycle has been dismantled.
Once again it should be remarked that the embodiments, too, of the kickstand with locking mechanism can be used independently of the constructions discussed above, on any cycle at all, and that for this reason the possibility is kept open of splitting these advantageous constructions from the patent application at hand and claiming them independently.